Cotrimoxazole Still Prevents Death in the Era of Antiretroviral Therapy in Asia

Published Tuesday, July 17, 2012

Cotrimoxazole (trimethoprim-sulfamethoxazole) is an antibiotic that is active against a wide range of bacteria, fungi, and parasites. In HIV-infected patients, it is recommended for all patients with severe immune suppression (CD4 counts below 200 cells/mm3) to prevent the occurrence of opportunistic infections such as Pneumocystis jiroveci pneumonia, or PCP. Using cotrimoxazole as a prophylactic medicine has also been shown to reduce deaths in patients who have severe immune suppression, even when antiretroviral therapy is available.

In spite of guidelines recommending cotrimoxazole prophylaxis and the wide availability and affordability of the drug it is not consistently used in resource-limited settings. TREAT Asia researchers investigated the use of this prophylaxis between 2003 and 2009 in the TREAT Asia HIV Observational Database (TAHOD).1 The analysis included a total of 4,050 patients, of whom 90 percent were taking antiretroviral therapy. It was found that among those with CD4 levels below 200 who should have been receiving prophylaxis, only around 60 percent received it over the study period, although this proportion increased from 58 percent in 2007 to 72 percent in 2009. This varied also by clinical site, with prophylaxis coverage ranging from as low as 30 percent in some centers to 100 percent in others.

During follow-up, 62 cases of PCP were diagnosed and 169 patients died. It was found that the risk of PCP diagnosis was not statistically different between patients receiving or not receiving prophylactic antibiotics. However, the risk of overall mortality was more than 10 times higher in patients not receiving prophylaxis. The survival benefit of prophylaxis was highest in patients with very low CD4 levels (below 50 cells/mm3), but remained significant for all patients with CD4 counts below 200 cells/mm3, and was also observed in patients with levels above 200 cells/mm3.

These findings confirm the importance of cotrimoxazole prophylaxis to prevent death in patients with immune suppression, even when taking antiretroviral therapy, and illustrate the need to continue efforts to offer this simple intervention to all eligible patients receiving HIV care in Asia.